Reconstruction or no reconstruction?

I was diagnosed with breast cancer a week ago and I am going to be having a mastectomy. I have now been faced with the decision of having reconstruction at the same time or not. I didn't even think about reconstruction all i wanted was to treat the cancer but now I feel I am going around in circles with my decision making. It is so much to take in and I keep reading pros and cons to both and if i I do which one is the best type of reconstruction. Dealing with the news I have breast cancer has been devestating news enough and worried I can think past the next few weeks to make the right decision for my future. I am 45 with two teenage boys. Any advice would be gratefully received